<template>
  <!-- 头部部分 -->
  <header class="header">
    <h1>todos</h1>
    <input  class="new-todo" @keyup.enter='add'    placeholder="请输入任务名称" autofocus v-model='todoName' />
  </header>
</template>

<script>
export default {
  data () {
    return {
      todoName:''
    }
  },
  methods: {
    add() {
      if(this.todoName.trim()==='') return alert('输入不能为空')
      this.$emit('add',this.todoName)
      this.todoName=''
    }
  },
}
</script>

<style></style>
